The Amazing Canadarm2

Crawling around the International Space Station like
an agile worm, the newest Canadian robotic arm will be essential
for building and maintaining the ISS.

April
18, 2001 -- Building a brand new space station is a big job.
Just ask the assembly crews of the International Space Station
(ISS). They have to attach modules weighing tons, extend solar
panels longer than a bus, and haul equipment to and from the
space shuttle. It sounds like these hardworking astronauts could
use a hand!

Now, thanks to the Canadian Space Agency (CSA), they're going
to get one.

When the space shuttle Endeavour blasts off on mission STS-100,
one of its passengers will be a new assistant for the crew of
the International Space Station -- an extraordinary robotic arm
called Canadarm2.

"Canadarm2 is a bigger, smarter and more grown-up version
of the shuttle's robotic arm," said Chris Lorenz, CSA's
manager of mission operations. "It's part of Canada's investment
in the space station program."

Above: This artist's concept shows the Canadian Space
Agency's Mobile Servicing System, which includes Canadarm2, a
truck-like base to shuttle the arm from one spot to another,
and a 15-jointed dexterous hand. [more
information]

Canadarm2 is surely big and strong, but it's not just a brute.
This next-generation robotic arm has some amazing tricks up its
sleeve. Consider, for example, the way it moves. Unlike the original
Canadarm, which is mounted just outside a shuttle's payload bay,
Canadarm2 won't be tied down to one spot. Each end of the new
arm has a hand that can grasp an anchor on the space station.
By flipping end-over-end between anchor points, Canadarm2 can
move around the ISS like an inchworm.

With seven joints, Canadarm2 is more maneuverable than its
predecessor on the shuttle and even more agile than a human arm.
This is important because the space station is a larger and more
complex environment than the shuttle's payload bay.

Astronauts will install Canadarm2 during
a series of spacewalks beginning on Day 4 of the STS-100 mission.
From inside Endeavour, pilot Jeff Ashby will use the shuttle's
robotic arm to lift Canadarm2's pallet from the payload bay.
He'll maneuver it toward the Destiny Lab module where the pallet
will latch on to a special cradle.

Left: Canadarm2, folded inside its pallet, awaits launch
on STS-100.

Next, mission specialists Chris Hadfield (a Canadian) and
Scott Parazynski will leave the shuttle's airlock and begin their
space walk. The pair will unwrap Canadarm2 from its insulating
blankets, attach power to the arm and loosen its restraining
bolts. By the end of the day, Canadarm2 will be ready to step
out of its pallet.

On Day 6 of the mission, the two space walkers will venture
out again. This time they will install a Power Data Grapple Fixture
(PDGF) -- that is, a handhold for Canadarm2-- on Destiny itself.
When the PDGF is ready, Canadarm2 will reach out from its pallet
and grab the space station. It'll be one small step for Canadarm2,
and an impressive leap for space robotics!

After a few limbering up exercises, Canadarm2 will hand its
pallet back to Canadarm -- a maneuver that scientists have dubbed
"the first-ever robotic handshake in space."

Once
deployed, Canadarm2's primary job will be space station assembly.

"On the very next mission, Canadarm2 will be used to
install the airlock," said Ken Podwalski, a CSA scientist
working with Lorenz. "So we are going from arrival to immediate
use on the subsequent mission. This is really the critical piece
to continue construction of the space station."

Right: Canadian Space Agency astronaut Chris Hadfield
will become the first Canadian to perform a space walk when he
helps install Canadarm2 during the STS-100 shuttle mission. [learn
more about Chris]

For the next few years, the space station's crew will control
Canadarm2 from two identical consoles (called "Robotic Workstations")
located inside the Destiny Lab. Eventually one of those workstations
will move to The Cupola -- a module tentatively scheduled for
launch in 2005. Like the window-studded "Ten Forward"
lounge on Star Trek's USS Enterprise, the Cupola --with
eight windows-- will provide astronauts a stunning view of the
space around the ISS. It's the perfect spot for direct viewing
of the robotic arm and shuttle payload operations.

The Canadian Space Agency has also built a ground control
center for Canadarm2 at the CSA's Saint-Hubert, Quebec, headquarters.
That facility is linked directly to NASA's Mission Control at
the Johnson Space Center in Houston, Texas. Crewmembers on board
the ISS will be the ones who actually control the arm. Personnel
in Quebec and Houston will offer real-time support and troubleshooting
while Canadarm2 operations are underway in space.

Canadarm2
is only the first installment of what the CSA refers to as the
space station's "Mobile Servicing System." The next
piece (slated for launch no earlier than 2002) will be the Mobile
Base System, or MBS -- literally a small truck that moves along
rails covering the exterior of the ISS.

Left: an artist's rendering of the Mobile Base System,
a movable platform that slides along rails on the Space Station's
main truss structure.

"After the MBS is in place, we'll be able to move the
Canadarm up and down the length of the space station," said
Lorenz. Compared to inchworming, riding the MBS will be a less
entertaining way to travel -- but much faster.

The final piece of the Mobile Servicing System will be the
Special Purpose Dexterous Manipulator, an attachment for one
end of Canadarm2. This so-called "Canada Hand" is itself
a highly advanced robot with two arms and sophisticated feedback
mechanisms that allow it to touch and feel much like a human
hand. Equipped with lights, a video camera and four tool holders,
the Hand will perform sophisticated operations like installing
batteries, power supplies and computers.

After
it arrives in orbit (no sooner than 2003) the Canada Hand will
be controlled by the ISS crew using one of the Robotic Workstations.
The Hand, which can wield very specialized tools and execute
delicate servicing tasks, could substantially reduce the amount
of time astronauts spend working "outdoors" in the
dangerous environment of space.

Right: an artist's rendering of the versatile Special
Purpose Dexterous Manipulator attached to the end of Canadarm2.

An inchworming space arm equipped with a robotic super-Hand?
It sounds like a wonderful Lego kit! Indeed, Canadarm2 consists
of many Lego-like "on-orbit replaceable units" (ORUs).
"You can basically take the arm apart in Lego fashion and
replace units as needed," added Podwalski.

It would seem to be a case of life imitating toys, but that
shouldn't come as a surprise. The designers of Canadarm2 --the
same engineers who built Dino the Dinosaur at Universal
Studios-- must be kids at heart to develop something so wonderful.

Water on the Space Station -- Science@NASA article: Rationing and recycling will
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In this article, Science@NASA explores where the crew will get
their water and how they will (re)use it.

Breathing Easy on the Space
Station --
Science@NASA
article:
Life support systems on the ISS provide oxygen, absorb carbon
dioxide, and manage vaporous emissions from the astronauts themselves.
It's all part of breathing easy in our new home in space.

Microscopic Stowaways on the
ISS -- Science@NASA
article:
Wherever humans go microbes will surely follow, and the Space
Station is no exception. This article discusses how the ISS will
keep microbes to a minimum.

The Science and Technology Directorate at NASA's
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